[binutils-gdb] gas: Print DWARF call frame insn name in SFrame warning message

[Jens Remus]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=bdde1b34c4b4c08fb7e431f28b33a4144ca86f2c

commit bdde1b34c4b4c08fb7e431f28b33a4144ca86f2c
Author: Jens Remus <jremus@linux.ibm.com>
Date:   Thu Jul 4 10:34:12 2024 +0200

    gas: Print DWARF call frame insn name in SFrame warning message
    
    SFrame generation prints the DWARF call frame instruction opcode in
    hexadecimal. Leverage get_DW_CFA_name to additionally print the
    DWARF call frame instruction name in human readable form, while also
    respecting fake CFI types. Use "(unknown)", if the DWARF call frame
    instruction name is not known.
    
    While at it use the terminology "instruction" for these DW_CFA_*, as
    suggested by Indu.
    
    This changes the following assembler SFrame generation warning message
    as follows:
    
    Old:
    Warning: skipping SFrame FDE due to DWARF CFI op 0x<hexval>
    
    New:
    Warning: skipping SFrame FDE; CFI insn <name> (0x<hexval>)
    
    gas/
            * gen-sframe.c (sframe_get_cfi_name): New function to get the
            DWARF call frame instruction name for a DWARF call frame
            instruction opcode.
            (sframe_do_cfi_insn): Use sframe_get_cfi_name to print the
            DWARF call frame instruction name for the DWARF call frame
            instruction opcode in the warning message.
    
    gas/testsuite/
            * gas/cfi-sframe/common-empty-1.d: Update expected SFrame
            warning message text for DWARF call frame insn name.
            * gas/cfi-sframe/common-empty-2.d: Likewise.
    
    Signed-off-by: Jens Remus <jremus@linux.ibm.com>

Diff:
---
 gas/gen-sframe.c                              | 49 ++++++++++++++++++++++++++-
 gas/testsuite/gas/cfi-sframe/common-empty-1.d |  2 +-
 gas/testsuite/gas/cfi-sframe/common-empty-2.d |  2 +-
 3 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/gas/gen-sframe.c b/gas/gen-sframe.c
index 238b76f88ed..116d1f48f78 100644
--- a/gas/gen-sframe.c
+++ b/gas/gen-sframe.c
@@ -1199,6 +1199,46 @@ sframe_xlate_do_gnu_window_save (struct sframe_xlate_ctx *xlate_ctx,
   return SFRAME_XLATE_OK;
 }
 
+/* Returns the DWARF call frame instruction name or fake CFI name for the
+   specified CFI opcode, or NULL if the value is not recognized.  */
+
+static const char *
+sframe_get_cfi_name (int cfi_opc)
+{
+  const char *cfi_name;
+
+  switch (cfi_opc)
+    {
+      /* Fake CFI type; outside the byte range of any real CFI insn.  */
+      /* See gas/dw2gencfi.h.  */
+      case CFI_adjust_cfa_offset:
+	cfi_name = "CFI_adjust_cfa_offset";
+	break;
+      case CFI_return_column:
+	cfi_name = "CFI_return_column";
+	break;
+      case CFI_rel_offset:
+	cfi_name = "CFI_rel_offset";
+	break;
+      case CFI_escape:
+	cfi_name = "CFI_escape";
+	break;
+      case CFI_signal_frame:
+	cfi_name = "CFI_signal_frame";
+	break;
+      case CFI_val_encoded_addr:
+	cfi_name = "CFI_val_encoded_addr";
+	break;
+      case CFI_label:
+	cfi_name = "CFI_label";
+	break;
+      default:
+	cfi_name = get_DW_CFA_name (cfi_opc);
+    }
+
+  return cfi_name;
+}
+
 /* Process CFI_INSN and update the translation context with the FRE
    information.
 
@@ -1274,7 +1314,14 @@ sframe_do_cfi_insn (struct sframe_xlate_ctx *xlate_ctx,
   /* An error here will cause no SFrame FDE later.  Warn the user because this
      will affect the overall coverage and hence, asynchronicity.  */
   if (err)
-    as_warn (_("skipping SFrame FDE due to DWARF CFI op %#x"), op);
+    {
+      const char *cfi_name = sframe_get_cfi_name (op);
+
+      if (!cfi_name)
+	cfi_name = _("(unknown)");
+      as_warn (_("skipping SFrame FDE; CFI insn %s (%#x)"),
+	       cfi_name, op);
+    }
 
   return err;
 }
diff --git a/gas/testsuite/gas/cfi-sframe/common-empty-1.d b/gas/testsuite/gas/cfi-sframe/common-empty-1.d
index 125612ff841..dbb48949c71 100644
--- a/gas/testsuite/gas/cfi-sframe/common-empty-1.d
+++ b/gas/testsuite/gas/cfi-sframe/common-empty-1.d
@@ -1,5 +1,5 @@
 #as: --gsframe
-#warning: skipping SFrame FDE due to DWARF CFI op 0xa
+#warning: skipping SFrame FDE; CFI insn DW_CFA_remember_state \(0xa\)
 #objdump: --sframe=.sframe
 #name: Uninteresting cfi directives generate an empty SFrame section
 #...
diff --git a/gas/testsuite/gas/cfi-sframe/common-empty-2.d b/gas/testsuite/gas/cfi-sframe/common-empty-2.d
index 59328fc1033..7b2ce3e8c79 100644
--- a/gas/testsuite/gas/cfi-sframe/common-empty-2.d
+++ b/gas/testsuite/gas/cfi-sframe/common-empty-2.d
@@ -1,5 +1,5 @@
 #as: --gsframe
-#warning: skipping SFrame FDE due to DWARF CFI op 0xe
+#warning: skipping SFrame FDE; CFI insn DW_CFA_def_cfa_offset \(0xe\)
 #objdump: --sframe=.sframe
 #name: SFrame supports only FP/SP based CFA
 #...